That's probably what IHOP had in mind when it tweeted about the holiday this morning. But things quickly got a lot weirder.

"If you have pancakes in your tum tum, does that make you a pancake mum mum? Happy Mother's Day to ALL the moms out there!" the pancake chain wrote, attaching a photo of an ultrasound with a ghostly stack of pancakes visible.

People had a whole lot to say about the joke. Some rushed to point out that the scan is supposed to show the uterus and other organs, not the stomach.

IHOP's marketing strategy of late has been described as "bold." It included, for instance, temporarily rebranding to the "International House of Burgers" last year, which the company said caused burger sales to quadruple.

The company did not immediately respond for comment.

It's not the first time that the two organs have been muddled. In 2015, an Idaho lawmaker made headlines after asking a physician expert a question implying that the stomach and uterus were connected. (The lawmaker has said he was trying to make a rhetorical point.)

But it's possible someone could believe that, author and sexual health expert Martha Kempner said in a Rewire article at the time.

"After all, most of us are told as children that we grew in our mommy's 'tummy,'" Kempner wrote. "Unless that oversimplification is corrected either by our parents or a sex ed class, misunderstandings can easily remain."

A woman's belly does protrude out during pregnancy. That's because the uterus expands out over the 40 week period to accomodate a growing fetus, pressing on organs like the stomach in the process.

After doing research that asked 63 people to map out organs in the body, Lancaster University's Adam Taylor has described the public's anatomical understanding as "sketchy."

Taylor's team's research has shown that only half of people can correctly locate the stomach's position, and they are currently working on data around the uterus.

Even so, "the stomach and uterus are not usually confused," he said in an email to Business Insider. "The stomach is a muscular structure in the gastrointestinal system, whereas the uterus is a muscular structure in the reproductive system." They are also located in different places in the body, with the stomach at a higher position than the uterus, he noted.

Understanding anatomy matters because better information about where symptoms are "can help in identifying when things aren't right and seeking appropriate medical help," Taylor wrote.